The project is to study the natural animal cancer patterns in a defined geographic area to glean any information that would be of use in understanding human cancer occurrence. Collection of case histories and specimens provide a source of histologically diagnosed animal cancer cases for epidemiologic studies. From these data, the following types of studies can be done: (1) Characterization of animal cancers such as incidence rates, including age-, sex- and breed-specific, (2) etiological studies such as seeking factors or variables that may be affecting the risk or occurrence of various cancers in animals and relating them to human cancer occurrence, (3) human-animal association studies such as whether there is increased human cancer in households where an animal with cancer has lived, (4) human-animal comparisons such as age- and sex-specific incidence rate patterns, (5) laboratory studies such as attempts to isolate oncogenic viruses from various tumors or other cancerous animal tissues, and (6) treatment evaluation studies such as evaluation of new treatment methods or approaches prior to application to man.